<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    'abc'.padStart(10);         // "       abc"
    'abc'.padStart(10, "foo");  // "foofoofabc"
    'abc'.padStart(6,"123465"); // "123abc"

    'abc'.padEnd(10);          // "abc       "
    'abc'.padEnd(10, "foo");   // "abcfoofoof"
    'abc'.padEnd(6, "123456"); // "abc123"
</script>
</html>